circadian clock

A team of researchers finds that people diagnosed with hypertension might want to match the time they take prescriptions with their sleep schedule. It might be better for the heart.

We mark our days by sunlight, with special receptors in our eyes that respond to light and help reset our body clocks each day. This man can't see, but is still a circadian wiz. Here's how.

Late-night coffee, tea or cola does more than keep you up, scientists say. The amount of caffeine in a double espresso can delay the internal clock in cells throughout your body by about 40 minutes.